Every flu season a global network of scientists attempts to identify several predominant flu strains and include them into the next season’s flu vaccine.
The objective of this research is describing the main antigenic and molecular features of influenza viruses involved in three consecutive seasons.
The prospect that a new influenza virus with a pandemic potential will emerge in humans is of particularly serious concern.
We still do not have sufficient understanding of influenza infection in humans to predict whether the H5N1 viruses will became established in humans and, if they do, they will retain their higly virulent phenotype. Therefore monitoring and studying the emerging viruses is important to limit an eventual pandemic.
Moreover laboratory - based influenza surveillance is important for identifying and isolating strains candidate to enter new vaccines, the main tool of primary prevention. Although viral isolation remains the basic step for the antigenic and molecular characterization of circulating strains, the introduction of molecular methods has enormously amplified the sensitivity of virological surveillance in recent years. The widespread use of sequencing allowed a better assessment of viral genetic variation.